See PIC iPod wav player for my FAT16 SD card reader.
Reads and plays mono CD quality (16bit 44k) or stereo 8bit 44k from SD cards.
Utilizes multiblock for fast sequential read and play of wav data.
Also data for Nokia GLCD pictures or scrolling menu.

The code was written based on information from the Microchip USB framework
and Jan Axelson's book, USB Mass Storage. Details on SD and MMC cards and
the FAT file system can be found there.
Does Jan's book have any insight on 4 bit Bus mode?
I have the CRC routine worked out but haven't had success with Bus mode yet.

Norm